On Dec 17, 2007, at 2:38 PM, Jeremy Carroll wrote:
> Jim Hendler wrote:
>> <flame on - but not at Matthew>
>
> without wishing to fan Jim's flames, ...
>
> one aspect I noted at the F2F was that there is this decidability
> litmus test there is some wiggle room, and the actual drivers for
> what was a compelling argument and what wasn't had to do with the
> use cases and customers who we each had in mind.
This is just about always the case. *All* OWL 1.1 features were
driven by user needs and implementor realizability. This is hardly an
strange design stance at the W3C!
However, you have made a very specific decidability argument, to wit,
that under just about any extension (e.g., of nary data predicates),
if I combine two files that meet all the decidability restrictions
then their union should also be decidable.
*This* notion of a "decidability requirement" has not been taken as a
hard requirement if only because there's no evidence that it was
*ever* a requirement: it's not true of OWL DL (simple roles,
datatypes). Thus, it doesn't make us *worse off*.
Data values are an explicit extensibility point of OWL.
[snip]
> So, as HP rep, I found the Oracle presentation compelling, much
> more compelling than most, because the Oracle customers and the HP
> customers are similar and doing similar things. However, none of
> the presentations were explicit in terms of customers,
This isn't true, or perhaps at best narrowly true (I've not reviewed
all the presentations per se). I've several times mentioned specific
users for Rich Annotations and N-ary datatypes. We brought into the
meeting users of both. (And not just "academic" users..both Alan and
esp. Sebastian are working in collaboration with Siemens on a
commercial project.)
> and we have made precious little advance on a use case and
> requirements document,
UC&R documents at the W3C very rarely track back to specific users,
so I don't see this as an advance.
> so that the hidden differences between us (the various members of
> this WG) in terms of what we are trying to do with OWL, for whom,
> and why, remain hidden.
[snip]
Nothing stops you (or Jim) from talking as explicitly about your
users as I do. Indeed, I encourage you to do so and have done so
frequently.
Cheers,
Bijan.